Negative glow device



Feb. 2, 1937. A. F. HENNINGER, JR 1 53 NEGATIVE GLOW DEVI CE Filed Jan. 11, 1935 2 Sheets Sheet 1 f ZZZ/61W Feb. 2, 1937. A HENNINGER; JR I 2,069,308

NEGATIVE GLOW DEVICE Filed Jan. '11, 1935 2 Sheets-Sheet 2 Patented Feb. 2, 1937 UNITED STATES PATENT OFFICE 10 Claims.

This invention relates tonegative glow display devices and particularly to an improved method of construction therefor by which elaborate negative glow display having greater structural rigidity and improved appearance can be manufactured at low cost, and operated with reduced current consumption.

Difliculty has been encountered heretofore in manufacturing negative glow displays having several electrodes connected to a common stem and mounted one above the other, due to the flexibility of the structure and the necessity of using numerous unsightly support wires to brace the electrodes. Additional difficulty also is encoun- 5 tered in insulating the connecting leads to the various electrodes. If insulating cement is used it must be applied with a brush after theassembly is complete. Likewise as a higher voltage is used with multi-electrode displays the insulating 20 cement frequently breaks down at some point where it is thin causing an unsightly are which consumes a portion or all of the current passed by the limiting resistor and results in-a diminution or elimination of the negative glow which 25 should cover the electrodes.

In a display of this type it is objectionable in many instances to use glass tubing overthe 'support wires to insulate them from each other and from electrodes of opposite polarity, as there is 30 practically always a portion of the wire-visible at the ends. If the ends are coated with insulating cement and the ends of the glass tubing sealed, fractures of the glass tubing are frequently encountered during the bombarding process while 35 the signs are being evacuated.

a My invention contemplates as one of its objects the use of a flat or curved sheet of mica or other suitable material upon which the electrodes are mounted. The preferred form of construction when using a tubular bulb or glass envelope of the same diameter throughout the major portion of its length, is to use a sheet of mica of such proportions that it is somewhat longer than the total length occupied by the display and of a width but slightly less than the inside diameter of the glass envelope into which the display is sealed. The electrodes of the display may be mounted on the mica by various means in the same display. For example one or'more electrodes may be mounted with their backsurfaces flat against the mica to eliminate the glow except from the front portion facing the observer and connection may be made by small wires passing through small perforations through the mica and end-welded to the back of any convenient part of the electrodes. Certain electrodes may be mounted so as to cover, or partly cover, other electrodes and connections may be made to such. an electrode by means of a wire surrounded and supported by insulating bushings passing through 5 the first electrodes and mica sheet and endwelded to the electrode.

It is readily apparent that by this construction electrodes can be mounted one above the other at a considerable height above the stem and still 10 have great mechanical rigidity. The flexibility of the mica sheet is decreased when the electrodes are attached and when sealed in the glass envelope the mica sheet will rest firmly against the side of the glass if moved even slightly from its central position. This simplifies the sealing process as the display is substantially centered in the bulb at all times with no attention from the operator. It likewise eliminates bent and broken displays due to careless handling and shocks received while being shipped.

In multi-electrode displays it is customary to use one or more common electrodes which glow the majority of the time while different electrodes of opposite polarity are so connected, singly or in groups, by a variable external switching means as to glow in conjunction with the common electrode or electrodes. With the above described construction wherein the connecting leads from the'electrodes are brought to the stem at the rear of the mica sheet the insulating problem of the connecting leads is practically eliminated as only the leads connecting to the main electrode or electrodes need to be insulated and in many instances no insulating cement is required when the main electrode is connected directly to the stem. This is due to the small area of the connecting leads causing a higher internal resistance between leads or between electrodes and leads than the resistance between the larger exposed electrodes of opposite polarity which are on the other side of the mica sheet. It is quite obvious that the electron flow will be between the large exposed electrodes facing the observer to the maximum amount permitted by the limiting resistor rather than between the small connecting leads at the back, one polarity of which is insulated, or between connecting leads at the back either bare or insulated and any of the front electrodes as in such a case the electron stream would have to pass completely around the edge of the mica sheet. v

A further advantage of the mica sheet is that it has sufficient reflecting properties .when used in the described manner to make the connecting leads in the back of the display practically invisible. A further advantage is that with its use the cylindrical shape of the glass envelope is less apparent and the display assumes the shape of the mica sheet, such as square or rectangular.

It is obvious that other comparatively inert insulating materials besides mica could be used successfully. It is likewise apparent that metal could also -be used bent in any shape or the edges bent at an angle or with reinforcing ribs. The use of metal, however, would prohibit mounting the electrodes flat against its surface as one of its purposes in this instance would be to act as a barrier or shield to any tendency of the electron flow to pass between any of the front elec trodes and the connecting leads at the rear. The electrodes therefore should be mounted slightly spaced from the front surface of the metal support with connecting leads from the electrodes passing through the metal shield and separated therefrom by means of the insulating bushings.

By use of this constructiondisplay signs which were simple to manufacture have been constructed having seven electrodes and having as many as ninety complete changes in appearance when used in conjunction with a simple switching arrangement. Without using the construction of the present invention such a device would obviously have so many conducting and support wires as to make it impractical to manufacture from a production viewpoint. Also so many visible wires would be so unsightly as to ruin its advertising value.

It is believed the further disclosure of this invention will be best understood from a detailed description thereof taken in connection with the accompanying drawings in which Fig. 1 is a face view of the device witha portion of the glass envelope broken away;

Fig. 2 is a view of the press and the electrodes and mounting sheet as viewed from the rear;

Fig. 3 is an edge view of the structure shown in Fig. 2, slightly enlarged;

Fig. 4 is a section substantially on line 4-4, of Fig. 1;

Fig. 5 is a section on line 5-5 of Fig. 2; and

Fig. 6 is a section through the device showing a modified form in which the insulating mounting plate and the electrodes are curved so that the device will be more readily apparent if viewed somewhat from the side.

Referring now to the drawings in which like reference characters indicate the same parts in the several views, l0 indicates the base of the tube or device which is formed of insulating 'material in the usual manner. Within the base is the stem or press ll of glass or other suitable material to which is joined the substantially tubular glass envelope 52. The mounting plate is of mica or other suitable material is arranged substantially diametrically across the tube l2 and forms the support for the various electrodes which are seen best in Fig. 1. What may be termed the main eiectrcde it in the present disclosure is in the general form of a bottle and its rear surface is substantially in engagementwith the mica mounting plate i3. A conducting lead it extends upwardly from the press H, passes through a small perforation E8 in the mica supporting plate, and is end-welded to the electrode i in an obvious manner.

The electrode i? is mounted in front of the electrode and may have any desired design thereon. T e conducting l a 58 extends to and is conne "'1 W156 The manner in which this is accomplished is best seen in Fig. 5. The lead i8 is provided at its upper end with a right angularly extending portion 59 which extends through a sleeve 20 of insulating material and is end-welded to the electrode I? at 2i. Secured to the portion G9 in any desired manner as by welding or riveting is a cross bar 22. Between the cross bar and the supporting plate 23 and surrounding the insulating sleeve 20 is an in sulating sleeve 23 and between the electrodes Hi and H is a similar insulating sleeve 24. Thus it will be seen that this structure not only acts to firmly support the electrode ll in spaced relation to the electrode it but also acts to hold the electrode i l firmly in engagement with the mica plate l3.

Another electrode 25 overlies the electrode i l and is supported in spaced relation thereto by a structure substantially the same as that shown in Fig. 5 just described. The right angularly extending portion 28 of the conducting medium is is joined to the conducting medium i8 by spotwelding or in any other desired manner.

Another electrode 27 which lies immediately under the XYZ electrode 28 is joined to the conducting lead 29 which extends through a perforation Bil in the mica plate and is end-welded to the electrode 21. The electrode 21 may be plain while the electrode 28 will preferably be provided with a cut-out design. The electrode 28 is joined to the conducting lead it through the medium of the branch 3! which is endwelded to the electrode 28 as before described.

The arrangement by which the connecting lead 3i is passed through the mica support #3 and the. back electrode 21 is substantially identical with that shown in Fig. 5 and therefore need not be further described.

In addition to the electrodes previously described there is an electrode 32 in the form of dancing elves, the rear surface of which is spaced from the mounting plate 13. The conductor 33 is connected to the electrode 32 by passing through a perforation in the mounting plate and being end-welded thereto as indicated at 34 in Fig. 3. overlying the electrode 32 is a plate 35 having substantially the same marginal contour as the electrode 32. .In fact these plates may be alike except the outer'plate 35 is preferably formed with certain perforations or openings therethrough while the electrode 32 is preferably imperforate. The plate 35 is supported in spaced relation to the mounting plate and electrode 32 by means of the pins or studs 36 and 3?. The pin 3% passes through the mounting plate 63, electrode H3 and electrode 32 and is joined to the plate 35. Pin 36 is insulated from the electrodes H3 and 32 in a manner similar to that disclosed in Fig. 5 and the various parts are held in spaced relation by the insulating sleeve 38 in a manner which will be readily understood. The pin 3'? passes through the mica mounting plate 53 and electrode 32 and is joined to the outer electrode 35. The pin 3? is insulated from the electrode 32 and the-parts are maintained in spaced relation by insulating sleeves as will be readily understood from the above description.

In Fig. 6 is shown a modification of the device of Fig. 1, similar parts in the two figures being represented by the same reference characters, except that primes (i are added inFig. 6. We have the envelope i2, within which the curved mounting plate At U3 appears the lower end of electrode 5 of 1, while overlying I 2,069,308 the electrode M are the electrode 32'. and the.

plate 35'. This construction may havecertain advantages over the form shown in Fig. 1 in that the mounting plate l3, being curved, the ends of it are normally in engagement with the interior surface of the envelope l2. This form also has the further advantage in that if the sign is viewed slightly from .the side rather than directly from in front it gives more nearly the impression of the curved surface of the bottle, etc. In other words, it appears somewhat more. natural. When, however, it is viewed from substantially directly in front it has about the same appearance as does the form shown in Fig. 1.

In accordance with previously disclosed methods of operation of signs of the character herein described, certain of the electrodes may be caused to glow at one time and other groups or combinations of them to glow at a different time. Thus considering the electrodes 21 and 28, the electrode 21 may be caused to glow while 28 remains dark in which case the design cut into the plate 28 will appear as illuminated from the rear plate, whereas, if the plate 28 is illuminated and the plate 21 dark the cut-out portions of plate or electrode .28 will appear dark while the portion surrounding them will be illuminated.

As to the plates 32 and 35 which represent the dancing elves the outer plate will at all times be unilluminated while the inner electrode .32 will be illuminated in which case there will be an illuminated margin observed about the edges of the outer plate 35 and the perforations through the outer plate 35 will be illuminated.

As to the electrodes l4 and 25 these may be either illuminated or dark at will, under the con trol of the interrupter or switching mechanism which will be employed in the operation of the device.

Having thus described my invention, what I claim as new and desire to secure by United States Letters Patent is:

1. In a negative glow device, .a tubular envelope of transparent material, a plurality of electrodes in said envelope, one of said electrodes overlying another, a curved sheet of insulating material of substantial area within said envelope and extending generally longitudinally thereof, means for supporting said electrodes from said sheet in insulated relation to each other all of said electrodes being on one side of said sheet, a press within said envelope, terminals extending from said press and conductors for electrically joining said electrodes to said terminals, said sheet having perforations therein through which said conductors pass, said conductors being positioned on the side of said sheet opposite to: said electrodes.

2. In a. negative glow device, an envelope, a plurality of electrodes in said envelope, a sheet of substantial area within said envelope having edge portions at opposite edges thereof adapted to engage the ,walls of the envelope, said sheet being the primary supporting element for the electrodes, means securing said electrodes to said sheet in insulated relation to each other,a press within said envelope, terminals extending from said press, and means for electrically joining said electrodes to said terminals.

3. In a negative glow device, an envelope of transparent material, a plurality of electrodes in said envelope, one of said electrodes overlying another, a sheet of substantial area within said envelope, having edge portions at opposite edges thereof adapted to engage the walls of the envelope, said sheet being the primary supporting element for the electrodes, means securing said electrodes to said sheet in insulated relation to each other, a press within said envelope, terminals extending from said press, and means for electrically joining said electrodes to said terminals.

4. In a negative glow device, an envelope of transparent material, a plurality of electrodes within said envelope, a sheet of insulating material of substantial area within said envelope and extending longitudinally thereof, having edge portions at opposite edges thereof adapted to engage the walls of the envelope, said sheet being the primary supporting elements for the electrodes, means securing said electrodes to said sheet in insulated relation to each other, a press within said envelope, terminals extending from said press, and means for electrically joining said electrodes to said terminals.

5. In a negative glow device, an envelope of transparent material, a plurality of electrodes within said envelope, one of said electrodes overlying another, a sheetof insulating material of substantial area within said envelope, having edge portions at opposite edges thereof adapted to engage the walls of the envelope, said sheet being the primary supporting element for the electrodes means securing said electrodes to said sheet in insulated relation to each other, a press within said envelope, terminals extending from said press, and means for electrically joining said electrodes to said terminals.

6. In a negative glow device, a tubular envelope of transparent material; a plurality of electrodes within said envelope, a sheet of insulating material of substantial area within said envelope and said envelope, having edge portions at opposite g edges thereof adapted to engage the walls of the envelope, said sheet being the primary supporting element for the electrodes, means securing said electrodes to said sheet in insulated relation to each other, a press within said envelope, terminals extending from said press, and means for electrically joining said electrodes to said terminals, said last named meanscomprislng conductors positioned on one side of said sheet, said electrodes being on the opposite side of said sheet. 8. In a negative glow device, an envelope of transparent material, a plurality of electrodes in said envelope, one of said electrodes overlying another, a sheet of substantial area within said envelope, having edge portions at opposite edges thereof adapted to engage the walls of the envelope, said sheet being the primary supporting element for the electrodes, means securing said electrodes to said sheet in insulated'relation to each other, a press within said envelope,

' terminals extending from said press, and means for electrically joining said electrodes to said terminals, said last named means comprising conductors positioned on one side of said sheet,

said electrodes being on the opposite side of said sheet, and said sheet having perforations therein through which the conductors p%s to the electrodes.

9. In a. negative glow device, a tubular envelope of transparent material, a plurality of electrodes within said envelope, a sheet of insulating'material of substantial area within said envelope and extending generally longitudinally thereof, having edge portions at opposite edges thereof adapted to engage the walls of the envelope, said sheet being the primary supporting element for the electrodes, means securing said electrodes to said sheet in-insulated relation to each other, a press within said envelope, terminals extending from said press, and means for electrically joining said 'nals.

electrodes to said terminals, one of said electrodes being mounted against said sheet.

10. In a negative glow device, a tubular envelope of transparent material, a plurality of electrodes in said envelope, a curved sheet of insulating material of substantial area within said envelope, having edge portions at opposite edges thereof adapted to engage the walls of the envelope, said sheet being the primary supporting element for the electrodes, means securing said electrodes to said sheet in insulated relation to each other, a press within said envelope, terminals extending from said press, and means for electrically joining said electrodes to said termi- ANDREW F. HENNINGER, JR. 

